Pneumatic-despatch-tube apparatus.



J. G. MAGLAREN.

PNEUMATIC DESPATGH TUBE APPARATUS.

APPLICATION FILED 11017.12, 1908.

Patented May 16, 1911.

UNITED STATES PATENT OFFICE.

JAMES G. MACLAREN, 0F HARRISON, NEW YORK, ASSIGNOR TO LAMSON CONSOLIDATED STORE SERVICE COMPANY, OF NEWARK, NEW JERSEY, A CORPORATION OF NEW JERSEY.

PNEUMATIC-DESPATCH-TUBE APPARATUS.

Specification of Letters Patent.

Patented May 16, 1911.

To all whom 'it may concern:

Be it known that I, JAMES G. MACLAREN,

of Harrison, in the county of Westchester and State of New York, have invented certain new and useful Improvements in Pneumatic-Despatch-Tube Apparatus, of which the followin is a specification.

My invention relates to improvements in pneumatic despatch tube apparatus and particularly to a combined vacuum and pressure system.

The object of this invention is to provide means for controlling a constantly operating blower connected with the tube system whereby either the high or low pressure connections of said blower will operate normally unloaded and upon the despatching of a carrier either the vacuum or pressure side of the blower may be thrown into communication with the tube system for driving carriers while the opposite side of the blower operates short circuited or unloaded.

Means are provided for throwing into operation with the tube system both sides of the blower when it is required to despatch carriers by vacuum and pressure simultaneously.

In the accompanying drawing is illustrated a form of construction embodying my invention showing the system in normal or non-operating position.

A represents a blower driven by a pulley B which is adapted to be connected with and driven by a constant speed electric motor. The low pressure side of the blower A is connected with the vacuum terminal E by the exhaust pipe The terminal E is controlled by the usual delivery valve E.

' The high pressure side of the blower A is connected with the pressure terminal F through transit tubeH and discharge pipe G.

J is a despatchin inlet for inserting carriers into the translt tube H for transmission to the delivery terminal F which is controlled by a spring retained valve F.

K is a valve covering despatching inlet J and is arranged to be opened by hand to insert a carrier therein, and to be locked closed against the air pressure by a suitable latch L.

The vacuum terminal E is connected by a transit tube M with the pressure terminal.

F. The exhaust pipe D transit tubes M and H and discharge pipe G form a complete circuit through the blower A. Located in the exhaust ipe D is an unloading device V for controqling the low pressure side of the blower said device being disclosed in my application for United States Letters Patent Ser. #432,800 filed May 14, 1908. Located in the discharge pipe G is an unloading device for controllingthe high pressure side of blower A and which is shown and described in another invention made by me for United States Letters Patent Ser. #427,356 filed April 16, 1908. The unloading device V comprises a casing 14 having an air chamber 15 therein connected with the pipe D through passage 13. 16 and 17 are ports for admitting air to the chamber 15, and 18 and 19 are valves normally open and adapted to control the admission of air through said ports 16 and 17 respectively. These valves 18 and 19 are mounted on the stem 20 which is reciprocally mounted in the hangers 21.

22 is a lever pivoted at its lower end 23, its upperend being bifurcated at 24: and adapted to straddle the pin 25 on stem 20 for operating valves 18 and 19.

53 is an armature secured to lever 22 and adapted to be operated by the magnet 52 of generator X through wire a magnet 52 wire 6 switch 54 and wire a back to the motor generator X.

34 is a diaphragm casing having mounted therein the dlaphragm 35, the stem A2 bemg connected to said diaphragm at its upper end and at its lower end carrying bridge piece 43. The chamber 37 beneath said diaphragm 35 is connected with the atmosphere through passage 40 controlled by the timing valve 41. 38 is a passage connecting said chamber 37 with the atmosphere and controlled by a flap .valve 39 to permlt a quick exhaust of air from said chamber 37 when diaphragm 35 drops. The chamber 36 above diaphragm 35 is connected with the chamber 15 through passages 31-, 32, and 33.

49 is a valve mounted on lever 47 which is pivoted at 48 and held normally closed by the spring 51. This valve 49 is adapted when opened to admit air to the passages 32 and 33. On the opposite end of the lever 47 is an armature 50 which is operated by the magnet 46 to open said valve 49. The magnet is in circuit with the motor generator X through wires 0, h, 9, contacts 45 and 44 and wires f and a.

27 is a, diaphragm mounted in casing 28 and which is open to the atmosphere on one side and on the other side communicates with chamber 2 which is connected with the passage 33. r

26 is a stem secured at one end to diaphragm 27, the opposite end of said stem having a slot 29 in which a pin 30 secured to lever 22 is mounted.

The unloading device P adapted to con trol the high pressure side of blower A is comprised of the casing 13 having a cham.

ber 14* therein connected with the discharge pipe G through the pipe 9. The chamber 14 is adapted to communicate with the atmosphere through ports 15 and 16 controlled by the valves 17 and 18 respec-' tively'. These valves are substantially balanced against the pressure in chamber 14 and are mounted on the rod 26 slidable in bearing 19 secured to the casing 13*.

20 is a lever pivotally mounted at 21, its upper end being slotted and adapted to operate rod 26' and valves 17 and 18 through the pin 22 connected with said rod.

23 is a spring secured at one end at 24 and at the other end at 25 to the lever 20*. This spring 23 is adapted to normally operate through the lever 20, pin 22 and rod 26 to hold the valves 17 and 18 normally opened to permit the discharge of the air from blower A through ports 15 and 16 to the atmosphere. 27 is a magnet and 28 is an armature for said magnet secured to the lever 20*. The magnet 27 a is in circuit with motor generator X and switch J? located at pressure despatching inlet J and pressure receiving terminal F.

32* represents an insulating rod movable in the hanger 33 and pivoted at one'end at 34 to lever 20. 35 is a contact piece secured to the opposite end of rod 32 and 36 is a similar contact piece mounted on insulator 37 movable in the casing 38. 39 is a spring mounted on the insulator 37 a and adapted to maintain slight tension on contact 36. These contacts 35 and 36 form a normally open switch which is adapted to be closed when magnet 27 a is energized.

The circuit through magnet 27 and switch J 2 is as follows: from motor generator X through wire k to said magnet 27 thence through wire Z, switch J and wire m back to motor generator X. The shunt circuit through magnet 27 and circuit breaker F? at the delivery terminal is as follows: from motor generator X through wire 7,0 magnet 27, wire 1' contacts 35" and 36*, wire 8 circuitbreaker F and wires t and m back to motor generator X.

The operation of the device is as follows: The blower A operates at a constant speed and the air is normally taken in through ports 16 and 17 and discharged through ports 15' and 16 in the direction indicated by the arrows. In despatching carriers from sub-station S to central station C the valve N is opened and the carrier inserted into the inlet 0 said valve N then being closed. The opening of valve N operates to momentarily close switch 54 which through circuits hereinbefore described energizes magnet 52 attracting armature 53 which acts through lever 22 and pin 25 and rod 20 to move valves 18 and 19 closing the ports 16 and 17 and cutting off the admission of air through said ports. .The air being taken from blower A and inlets 15 and 16 through discharge pipe G transmission tube H and transit tube M back to the blower A through exhaust pipe D, driv-' ing the carrier through the tube M toward the central station C. In the meantime the increased vacuum in chamber 15 acts through passages 31 and 32 and 33.and chamber 2 to hold diaphragm 27 back retaining valves 18 and 19 closed against the atmospheric pressure. The vacuum also acting through passages 31, 32 and 33 and chamber 36 moves the diaphragm 35 gradu ally upward, due to the passage of air through the restricted opening 40 to chamber 37 beneath said diaphragm 35 causing .the bridge piece 43, when said diaphragm 35 has reached its highest position, to engage the contacts 44 and 45 controlling the circuit through and energizing the magnet 46. The armature 50 as now attracted by said magnet and through lever 47 opens the valve 49 against the tension of spring 51 admitting air to the passages 32 and 33 and chambers 2 and 36. The diaphragm is "returned to normal position by means of the atmospheric pressure acting upon the valve 18 which has greater area than valve 19-. causing said valves to open switchingthe circuit of air through chamber 15 pipe D to blower A. In the meantime the air entering valve 49 allows the diaphragm 35 and bridge piece 43 to drop, breaking the circuit through magnet 46 thereby releasing the armature 5 and permitting the spring 51 to close valve 49. By the time 18 and 19 have been opened in the manner described the carrier has delivered through valve E at the central station C. The adjustable timing screw 41 is adapted to be regulated to time the duration of the closure 0t valves 18 and 19 to the interval necessary for the proper transmission and delivery of the carrier.

In despatching a carrier from station 0 to the substation S the, latch L 1 the central moved releasing the valve K when the operator inserts a carrier into the inlet J closing said valve K which is locked by the latch L. The switch J 2 is momentarily closed and acts through circuits hereinbefore described to energize magnet 27 attracting armature 28 closing valves 17 and 18 through lever 20. The air is now taken through exhaustpipe D andinlet-s 16 and 17 through blower A thence through discharge pipe G to transit tube H driving the carrier toward the substation S. In" the meantime the movement of lever 20 acting through rod 32 moves contact 35 against contact 36? closing the shunt circuit through magnet 27 and circuit breaker F causing magnet 27 to remain energized hereby holding valves 17 a'nd'18 closed.

Vhen the carrier discharges through valve F at sub-station S circuit breaker F is operated breaking the circuit through and denergizing magnet 27 permitting valves 17 and 18* to be thrown open by action of spring 23 allowing the air through blower A to discharge through ports l5 and 16 to the atmosphere. It will thus be seen that the blower unloading connections with the atmosphere are independently operated, that is, when no carriers are being transmitted both the connections V and P are open to the atmosphere, but when a carrier is despatched from station C to station S the connection P is closed to the atmosphere while the connection V remains open. If a carrier is despatched fromstation S to station C the connection V is closed and the connection P remains open.

Having thus described my invention and set forth a construction embodying the same,

what I claim as new and desire to secure by tus, a tube for the transmission of carriers,

a blower or pump, avacuum connection between one end of said transmission tube and the inlet of said blower or pump, a pressure connection between the opposite end of said tube and the outlet of said blower or pump thereby forming a continuous circuit through said transmission tube and said blower or pump, means normallyfconnect-ing eachof said connections with the atmosphere to permit said blower or pump to operate unloaded, and means for independently controlling said. connections with the atmosphere to create a current of air through said transmission tube for driving carriers.

2. In a pneumatic despatch tube apparatus, a tube for the transmission of carriers, a blower or pump, a "acuum connection between one end of said transmission tube and the inlet of said blower or pump, a pressure connection between the opposite end of said tube and the outlet of said blower or pump thereby forming a continuous circuit through said transmission tube and said blower or pump, means normally connecting each of said connections with the atmosphere to permit said blower or pump to operate unloaded, means for independently controlling said connections with the atmosphere'to create a current of air through said transmission tube for driving carrlers, and means for timing the switching of said air current to the atmosphere.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses, this seventh day of November A. D. 1908.

JAMES G. MACLAREN.

Witnesses:

ELSIE MACLAREN, ARTHUR C. MUHLHALM. 

